This library provides a very simple extension to IO capabilities as provided by Arduino libraries.

AnalogInput class

This class may be used to perform common tasks while managing analog input, as we can see in the following example:

#include <oacio.h>

#define ROTARY_PIN 4

OAC::AnalogInput rotary(ROTARY_PIN);

void loop() {
  if (rotary.isChanged()) {
     long value =, 20);
     // Do something with the value

First of all, we declare our analog input variable using OAC::AnalogInput type. In the constructor, we pass the analog pin our potentiometer is connected to. In the loop() function, we may invoke isChanged() method on the AnalogInput object to know whether it has changed its value. If so, we can map the current value by invoking the map() method. Its arguments indicate the lower and upper limit of the range the analog value is mapped. In this example, a minimum value in the potentiometer would be mapped to 0 while the maximum value would be mapped to 20. After that, we can use the read value to perform some action (typically send a command to the simulator).

The isChanged() method accepts an optional argument of long type indicating the tolerance while detecting changes in the analog input. Some potentiometers are not very precise, and when they are stopped in some positions the value read by Arduino is not constant, dancing some units above and below. By default, this tolerance value is set to 16. If you still experiment that isChanged() returns true without moving the potentiometer, you should increase this value.

AnalogInput class also provides a read() method that returns the raw value as read from the analog pin. Nevertheless, you would likely find map() method more useful for your purposes.

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